scholarly journals The origins of modern biodiversity on land

2010 ◽  
Vol 365 (1558) ◽  
pp. 3667-3679 ◽  
Author(s):  
Michael J. Benton
Keyword(s):  
Regional Scale ◽  
Global Scale ◽  
Scale Model ◽  
Time Range ◽  
Geological Time ◽  
New Methods ◽  
Evolution Of Life ◽  
History Of ◽  
Extinction Events ◽  
Mass Extinction Events

Comparative studies of large phylogenies of living and extinct groups have shown that most biodiversity arises from a small number of highly species-rich clades. To understand biodiversity, it is important to examine the history of these clades on geological time scales. This is part of a distinct ‘phylogenetic expansion’ view of macroevolution, and contrasts with the alternative, non-phylogenetic ‘equilibrium’ approach to the history of biodiversity. The latter viewpoint focuses on density-dependent models in which all life is described by a single global-scale model, and a case is made here that this approach may be less successful at representing the shape of the evolution of life than the phylogenetic expansion approach. The terrestrial fossil record is patchy, but is adequate for coarse-scale studies of groups such as vertebrates that possess fossilizable hard parts. New methods in phylogenetic analysis, morphometrics and the study of exceptional biotas allow new approaches. Models for diversity regulation through time range from the entirely biotic to the entirely physical, with many intermediates. Tetrapod diversity has risen as a result of the expansion of ecospace, rather than niche subdivision or regional-scale endemicity resulting from continental break-up. Tetrapod communities on land have been remarkably stable and have changed only when there was a revolution in floras (such as the demise of the Carboniferous coal forests, or the Cretaceous radiation of angiosperms) or following particularly severe mass extinction events, such as that at the end of the Permian.

scholarly journals A comprehensive history of climate and habitat stability of the last 800&thinsp,000 years

2019 ◽  
Author(s):  
Mario Krapp ◽  
Robert Beyer ◽  
Stephen L. Edmundson ◽  
Paul J. Valdes ◽  
Andrea Manica
Keyword(s):  
Climate Model ◽  
Temporal Dynamics ◽  
Global Climate ◽  
Global Climate Model ◽  
Regional Scale ◽  
Geological Time ◽  
Comprehensive Overview ◽  
Long Term Stability ◽  
History Of

Abstract. A detailed and accurate reconstruction of the past climate is essential in understanding the interactions between ecosystems and their environment through time. We know that climatic drivers have shaped the distribution and evolution of species, including our own, and their habitats. Yet, spatially-detailed climate reconstructions that continuously cover the Quaternary do not exist. This is mainly because no paleoclimate model can reconstruct regional-scale dynamics over geological time scales. Here we develop a statistical emulator, the Global Climate Model Emulator (GCMET), which reconstructs the climate of the last 800 000 years with unprecedented spatial detail. GCMET captures the temporal dynamics of glacial-interglacial climates as an Earth System Model of Intermediate Complexity would whilst resolving the local dynamics with the accuracy of a Global Climate Model. It provides a new, unique resource to explore the climate of the Quaternary, which we use to investigate the long-term stability of major habitat types. We identify a number of stable pockets of habitat that have remained unchanged over the last 800 thousand years, acting as potential long-term evolutionary refugia. Thus, the highly detailed, comprehensive overview of climatic changes through time delivered by GCMET provides the needed resolution to quantify the role of long term habitat change and fragmentation in an ecological and anthropological context.

scholarly journals Post-Cretaceous bursts of evolution along the benthic-pelagic axis in marine fishes

2018 ◽  
Vol 285 (1893) ◽  
pp. 20182010 ◽  
Author(s):  
Emanuell Ribeiro ◽  
Aaron M. Davis ◽  
Rafael A. Rivero-Vega ◽  
Guillermo Ortí ◽  
Ricardo Betancur-R
Keyword(s):  
Morphological Variation ◽  
Mass Extinction ◽  
Marine Fishes ◽  
Ecological Opportunity ◽  
Pelagic Habitat ◽  
History Of ◽  
Evolutionary Radiations ◽  
Extinction Events ◽  
Mass Extinction Events ◽  
Lineage Diversification

Ecological opportunity arising in the aftermath of mass extinction events is thought to be a powerful driver of evolutionary radiations. Here, we assessed how the wake of the Cretaceous–Palaeogene (K-Pg) mass extinction shaped diversification dynamics in a clade of mostly marine fishes (Carangaria), which comprises a disparate array of benthic and pelagic dwellers including some of the most astonishing fish forms (e.g. flatfishes, billfishes, remoras, archerfishes). Analyses of lineage diversification show time-heterogeneous rates of lineage diversification in carangarians, with highest rates reached during the Palaeocene. Likewise, a remarkable proportion of Carangaria's morphological variation originated early in the history of the group and in tandem with a marked incidence of habitat shifts. Taken together, these results suggest that all major lineages and body plans in Carangaria originated in an early burst shortly after the K-Pg mass extinction, which ultimately allowed the occupation of newly released niches along the benthic-pelagic habitat axis.

scholarly journals The biogeographical imprint of mass extinctions

2018 ◽  
Vol 285 (1878) ◽  
pp. 20180232 ◽  
Author(s):  
Ádám T. Kocsis ◽  
Carl J. Reddin ◽  
Wolfgang Kiessling
Keyword(s):  
Mass Extinction ◽  
Marine Species ◽  
Mass Extinctions ◽  
Marine Life ◽  
Extinction Rates ◽  
Evolution Of Life ◽  
Severe Reduction ◽  
Permian Extinction ◽  
Extinction Events ◽  
Mass Extinction Events

Mass extinctions are defined by extinction rates significantly above background levels and have had substantial consequences for the evolution of life. Geographically selective extinctions, subsequent originations and species redistributions may have changed global biogeographical structure, but quantification of this change is lacking. In order to assess quantitatively the biogeographical impact of mass extinctions, we outline time-traceable bioregions for benthic marine species across the Phanerozoic using a compositional network. Mass extinction events are visually recognizable in the geographical depiction of bioregions. The end-Permian extinction stands out with a severe reduction of provinciality. Time series of biogeographical turnover represent a novel aspect of the analysis of mass extinctions, confirming concentration of changes in the geographical distribution of benthic marine life.

scholarly journals Meteorites that produce K-feldspar-rich ejecta blankets correspond to mass extinctions

2021 ◽  
pp. jgs2021-055
Author(s):  
M. J. Pankhurst ◽  
C. J. Stevenson ◽  
B. C. Coldwell
Keyword(s):  
Cloud Microphysics ◽  
Ice Nucleation ◽  
Mass Extinctions ◽  
Geological Time ◽  
Content Type ◽  
Meteorite Impacts ◽  
Cloud Dynamics ◽  
Supplementary Material ◽  
Extinction Events ◽  
Mass Extinction Events

Meteorite impacts load the atmosphere with dust and cover the Earth's surface with debris. They have long been debated as a trigger of mass extinctions through Earth's history. Impact winters generally last <100 years, whereas ejecta blankets persist for 103-105 years. Here we show that only meteorite impacts that emplaced ejecta blankets rich in K-feldspar (Kfs) correlate to Earth system crises (n=11, p<0.000005). Kfs is a powerful ice-nucleating aerosol yet is normally rare in atmospheric dust mineralogy. Ice nucleation plays an important role in cloud microphysics, which modulates global albedo. A conceptual model is proposed whereby the anomalous prevalence of Kfs is posited to have two key effects on cloud dynamics: 1) reducing the average albedo of mixed-phase cloud, which effected a hotter climate; 2) weakening of the cloud albedo feedback, which increased climate sensitivity. These mechanisms offer an explanation as to why this otherwise benign mineral is correlated so strongly with mass extinction events: every K-feldspar-rich ejecta blanket corresponds to a severe extinction episode over the past 600 Myr. This model may also explain why many kill mechanisms only variably correlate with extinction events through geological time: they coincide with these rare periods of climate destabilization by atmospheric Kfs.Supplementary material:https://doi.org/10.6084/m9.figshare.c.5690646

Geology and Evolution

2019 ◽  
pp. 75-106
Author(s):  
Bill Jenkins
Keyword(s):  
Natural History ◽  
Geological History ◽  
Geological Time ◽  
Directional Model ◽  
The Earth ◽  
Evolution Of Life ◽  
History Of ◽  
English Speaking ◽  
English Speaking World ◽  
Life On Earth

The dominant school of geology in Edinburgh in the early nineteenth century was that of the followers of the German mineralogist Abraham Gottlob Werner. His most important disciple in the English-speaking world was Edinburgh’s professor of natural history, Robert Jameson. The Wernerians believed that the history of the earth was fundamentally directional; they believed the earth started out as a ball of hot fluid from which the different rocks that now form the crust of the planet gradually precipitated out over geological time. It is argued in this chapter that this directional model of the geological history of the earth was peculiarly compatible with a progressive model of the history of life on earth. The changes in the physical condition of the earth over geological time were seen by some Wernerian geologists as driving the evolution of life.

scholarly journals Concurrent origins of the genetic code and the homochirality of life, and the origin and evolution of biodiversity. Part I: Observations and explanations

2015 ◽  
Author(s):  
Dirson Jian Li
Keyword(s):  
Genetic Code ◽  
Early History ◽  
Mass Extinctions ◽  
Genome Sequences ◽  
Origin And Evolution ◽  
New Methods ◽  
Evolution Of Life ◽  
History Of ◽  
Technical Details ◽  
Recruitment Order

The post-genomic era has brought opportunities to bridge traditionally separate fields on early history of life. New methods promote a deeper understanding of the origin of biodiversity. Relative stabilities of base triplexes are able to regulate base substitutions in triplex DNAs. We constructed a roadmap based on such a regulation to explain concurrent origins of the genetic code and the homochirality of life. Based on the recruitment order of codons in the roadmap and the complete genome sequences, we reconstructed the three-domain tree of life. The Phanerozoic biodiversity curve has been reconstructed based on genomic, climatic and eustatic data; this result supports tectonic cause of mass extinctions. Our results indicate that chirality played a crucial role in the origin and evolution of life. Here is Part I of my two-part series paper; technical details are in Part II of my paper (see “Concurrent origins of the genetic code and the homochirality of life, and the origin and evolution of biodiversity. Part II: Technical appendix” on bioRxiv).

scholarly journals GMD perspective: The quest to improve the evaluation of groundwater representation in continental- to global-scale models

2021 ◽  
Vol 14 (12) ◽  
pp. 7545-7571
Author(s):  
Tom Gleeson ◽  
Thorsten Wagener ◽  
Petra Döll ◽  
Samuel C. Zipper ◽  
Charles West ◽  
...  
Keyword(s):  
Model Evaluation ◽  
Land Surface ◽  
Large Scale ◽  
Groundwater Resources ◽  
Regional Scale ◽  
Global Scale ◽  
Expert Elicitation ◽  
Data Availability ◽  
Scale Model ◽  
Scale Models

Abstract. Continental- to global-scale hydrologic and land surface models increasingly include representations of the groundwater system. Such large-scale models are essential for examining, communicating, and understanding the dynamic interactions between the Earth system above and below the land surface as well as the opportunities and limits of groundwater resources. We argue that both large-scale and regional-scale groundwater models have utility, strengths, and limitations, so continued modeling at both scales is essential and mutually beneficial. A crucial quest is how to evaluate the realism, capabilities, and performance of large-scale groundwater models given their modeling purpose of addressing large-scale science or sustainability questions as well as limitations in data availability and commensurability. Evaluation should identify if, when, or where large-scale models achieve their purpose or where opportunities for improvements exist so that such models better achieve their purpose. We suggest that reproducing the spatiotemporal details of regional-scale models and matching local data are not relevant goals. Instead, it is important to decide on reasonable model expectations regarding when a large-scale model is performing “well enough” in the context of its specific purpose. The decision of reasonable expectations is necessarily subjective even if the evaluation criteria are quantitative. Our objective is to provide recommendations for improving the evaluation of groundwater representation in continental- to global-scale models. We describe current modeling strategies and evaluation practices, and we subsequently discuss the value of three evaluation strategies: (1) comparing model outputs with available observations of groundwater levels or other state or flux variables (observation-based evaluation), (2) comparing several models with each other with or without reference to actual observations (model-based evaluation), and (3) comparing model behavior with expert expectations of hydrologic behaviors in particular regions or at particular times (expert-based evaluation). Based on evolving practices in model evaluation as well as innovations in observations, machine learning, and expert elicitation, we argue that combining observation-, model-, and expert-based model evaluation approaches, while accounting for commensurability issues, may significantly improve the realism of groundwater representation in large-scale models, thus advancing our ability for quantification, understanding, and prediction of crucial Earth science and sustainability problems. We encourage greater community-level communication and cooperation on this quest, including among global hydrology and land surface modelers, local to regional hydrogeologists, and hydrologists focused on model development and evaluation.

Morphologic and taxonomic history of Paleozoic ammonoids in time and morphospace

Paleobiology ◽  
2008 ◽  
Vol 34 (1) ◽  
pp. 128-154 ◽  
Author(s):  
W. B. Saunders ◽  
Emily Greenfest-Allen ◽  
David M. Work ◽  
S. V. Nikolaeva
Keyword(s):  
Mass Extinction ◽  
Evolutionary History ◽  
Large Scale ◽  
Taxonomic Diversity ◽  
Mass Extinctions ◽  
History Of ◽  
Morphologic Variation ◽  
Components Analysis ◽  
Extinction Events ◽  
Mass Extinction Events

Principal components analysis (PCA) of 21 shell parameters (geometry, sculpture, aperture shape, and suture complexity) in 597 L. Devonian to L. Triassic ammonoid genera (spanning ~166 Myr) shows that eight basic morphotypes appeared within ~20 Myr of the first appearance of ammonoids. With one exception, these morphotypes persisted throughout the Paleozoic, occurring in ~75% of the ~5-Myr time bins used in this study. Morphotypes were not exclusive to particular lineages. Their persistence was not just a product of phylogenetic constraints or longevity, and multiple iterations of the same morphotypes occurred at different times and in different groups. Although mass extinction events severely condensed the range of morphologic variation and taxonomic diversity, the effects were short lived and most extinct morphotypes were usually iterated within 5 Myr. The most important effect of mass extinctions on ammonoid evolutionary history seems to have been their role in large scale taxonomic turnovers; they effectively eliminated previously dominant orders at the Frasnian/Famennian (F/F) (Agoniatitida), the Devonian/Mississippian (D/M) (Clymeniida), and the Permian/Triassic (P/T) (Goniatitida and Prolecanitida) extinctions. Survivors varied from two (P/T) to four (D/M) and five genera (F/F). These events generated sharp reductions in morphologic disparity at the D/M (58%) and at the P/T (59%), but there was a net increase at the F/F (38%). There was no obvious survival bias for particular morphotypes, but 64% are interpreted to have beenNautilus-like nektobenthic. The recurrence of particular combinations of morphology and their strong independence of phylogeny are strong arguments for functional constraint. Intervals between mass extinctions seem to have been relatively static in terms of morphotype numbers, in contrast to numbers of genera. Significant decreases in genus diversity (54%) and morphologic disparity (33%) commenced in the mid-Permian (Wordian/Capitanian boundary), well before the final P/T event.

scholarly journals ΙΣΤΟΡΙΑ, ΦΙΛΟΣΟΦΙΑ ΚΑΙ ΕΦΑΡΜΟΓΗ ΤΩΝ ΠΑΓΚΟΣΜΙΩΝ ΣΤΡΩΜΑΤΟΤΥΠΩΝ ΚΑΙ ΤΩΝ ΑΠΟΛΥΤΩΝ ΟΡΙΩΝ. ΠΡΟΣΦΑΤΕΣ ΑΝΑΟΕΩΡΗΣΕΙΣ ΤΗΣ ΓΕΩΛΟΓΙΚΗΣ ΧΡΟΝΙΚΗΣ ΚΛΙΜΑΚΑΣ

2006 ◽  
Vol 39 (1) ◽  
pp. 28
Author(s):  
Μ. Δ. Δερμιτζάκης
Keyword(s):  
Time Scale ◽  
Global Scale ◽  
Quality Of Data ◽  
Geological Time ◽  
Geological Time Scale ◽  
New Methods ◽  
Science Community ◽  
University Of Oslo ◽  
The University

In the last 150 years, the limits of the so called "formal" geochronological/ chronostratigraphical units were determined by several rock researchers using geohistorical events in several ways. The lack of standardisation made them useless for a global scale correlation. During the last two decades, the development of the field and laboratories techniques, the studies of radiogenic and stable isotopes, the improved evaluation of fossil files, the evaluation of paleomagnetic data and the application of cyclostratigraphy, improved the quality of data and contributed to the creation of the most upto-date International Chronostratigraphic Scale, including new subdivisions and determination of the boundaries of geological periods. The compiled New Geological Time Scale GTS 2004 integrates the most recent results of these new methods and was constructed by the International Union of Stratigraphy (ICS), in 2004, presiding F.M. Gradstein, from the University of Oslo, along with 38 other specialists. The new revised Geological Scale encompasses selected new methods that provide the most reliable information. The last Geological Time Scale incorporates important changes and is based on the application of the Global boundary Stratotype Section and Point (GSSP). Almost 50 GSSP have been defined up to now. Despite the enormous efforts for the construction of the most complete Geological Time Scale, a modified version needs the support and consent of the entire geological science community.

scholarly journals Mesozoic mass extinctions and angiosperm radiation: does the molecular clock tell something new?

Geologos ◽  
2012 ◽  
Vol 18 (1) ◽  
pp. 37-42 ◽  
Author(s):  
Dmitry Ruban
Keyword(s):  
Molecular Clock ◽  
Global Scale ◽  
Flowering Plants ◽  
Mass Extinctions ◽  
Geological Time ◽  
Late Mesozoic ◽  
Environmental Perturbation ◽  
History Of

Mesozoic mass extinctions and angiosperm radiation: does the molecular clock tell something new?Angiosperms evolved rapidly in the late Mesozoic. Data from the genetic-based approach called ‘molecular clock’ permit an evaluation of the radiation of flowering plants through geological time and of the possible influences of Mesozoic mass extinctions. A total of 261 divergence ages of angiosperm families are considered. The radiation of flowering plants peaked in the Albian, early Campanian, and Maastrichtian. From the three late Mesozoic mass extinctions (Jurassic/Cretaceous, Cenomanian/Turonian, and Cretaceous/Palaeogene), only the Cretaceous/Palaeogene event coincided with a significant, abrupt, and long-term decline in angiosperm radiation. If their link will be further proven, this means that global-scale environmental perturbation precluded from many innovations in the development of plants. This decline was, however, not unprecedented in the history of the angiosperms. The implication of data from the molecular clock for evolutionary reconstructions is limited, primarily because this approach deals with only extant lineages.

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